Apparatus for heat-treating elongated tubular material

ABSTRACT

Apparatus for treating elongated tubular material comprising heating the material, prior to a further working thereof, first by subjecting the material to a stationary heat source while rotating the material, and then by oscillating a source of heat substantially in the direction of length of the material while rotating the material.

United States Patent [51] Int. Cl 1. C03b 29/00 I72] Inventors MichaelLatham;

Alexander Bryan l-laswell, both ol Durham [50] Field of Search 65/ l 09,County, England 110, 120, 271, 272, 274, 276, 281, 292 I21] Appl. No.819,629 [22] Filed Apr. 28, 1969 References Cited [45] Patented Sept.21, 1971 UNITED STATES PATENTS 1 1 Ahblsncc 2232 ga gsg f g Llmlted3,186,819 6/1965 Thorington Ct al. 65/109 x 32 Priority AP 30 9 PrimaryExaminerArthur D. Kellogg 33 Great Britain Attorney-Waters, Roditi,Schwartz & Nissen 31 20519/68 ABSTRACT: Apparatus for treating elongatedtubular materi- [54] s igzfiigfiigg ft ELONGATED al comprising heatingthe material, prior to a further working 9 Cl im 4D thereof, first bysubjecting the matenal to a stationary heat a rawmg source whilerotating the material, and then by oscillatmg a [52] US. Cl 65/271,source of heat substantially in the direction of length of the 65/1 10,65/272, 65/274 material while rotating the material.

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' SHEET 2 UF 2 APPARATUS FOR HEAT-TREATING ELONGATED TUBULAR MATERIALThis invention relates to methods of, and apparatus for, treatingelongated tubular material.

According to one aspect of the present invention there is provided amethod of treating elongated. tubular material comprising heating thematerial, prior to a further working thereof, first by subjecting thematerial to a stationary heat source whilst rotating the material, andthen by oscillating a source of heat substantially in the direction oflength of the material whilst rotating the material.

According to another aspect of the present invention there is providedan apparatus for treating elongated tubular material comprising meansfor rotating the tubular material, a first source of heat for heatingsaid tubular material whilst the material is rotating, this first sourcebeing arranged to be stationary during operation, a second source ofheat, and means for oscillating this second source of heat substantiallyin the direction of length of said tubular material whilst said tubularmaterial is rotating.

For a better understanding of the invention and to show how the same maybe carried into effect, reference will now be made, by way of example,to the accompanying drawings, in which:

FIG. 1 is a diagrammatic end view of a part of an apparatus for bendingelongated glass tubing, in which part the tubing is heated prior tobending,

FIG. 2 is a diagrammatic side view, in the direction of arrow ll of FIG.1, of the apparatus part shown in FIG. 1,

FIG. 3 is a diagrammatic front view of a bending jig of the apparatusfor bending glass tubing, and

FIG. 4 is a diagrammatic sectional side view, in the direction of arrowIV of FIG. 3 and on a larger scale, of a glass tube holder (not shown inFIG. 3) and a detail of the bending jig, some parts of the jig beingomitted for the sake of clarity.

The apparatus for bending elongated glass tubing, shown in the Figures,includes three pairs of glass tube holders, one such holder 1 beingshown best in FIG. 4. Each holder 1 is able releasably to grip one endof a glass tube 2 by means of a toggle clamp 3 secured at one end of ahollow shank l of the holder 1. An aperture 4 in the shank 1' permitsair to be blown into the glass tube 2 secured in the holder. Each shank1' has secured to it a collar 5.

The collars 5 of a pair of holders 1 attached one to each end of a glasstube 2 to be bent can be located in one or other of two slotted members6 of the bending jig shown best in FIG. 3. This jig consists of avertical plate 7 on one vertical surface of which are mounted two arms 8for pivoting about a common horizontal pivot 9. These arms 8 can befixed at various angles relative to each other utilizing fixing holes A,or can be detached from the pivot 9 and each mounted vertically, spacedapart, utilizing holes 10B. This latter facility is utilized if a lengthof tubing is to be bent to a U-configuration. Guides 11 extend alongeach side of the outer portion of each arm 8. The guides 11 of each arm8 contain a holder nest 12 which carries the slotted member 6 of the armand which can be clamped in any desired position along the guides 11 bya clamp 13. The outer and inner ends of each nest 12 are formed by walls14 and 15 extending across the arm 8 and having slots in their upperedges for receiving the shank l of a holder 1. Each nest 12 also carriesa hollow block 16 connected to a source of air under pressure via a footoperated valve (not shown) and by means of which air can be blown intothe aperture 4 of a shank 1 supported in the nest 12,

The apparatus further includes equipment for heating glass tubing priorto bending the tubing in the bending jig. This equipment is shown inFIGS. 1 and 2 and includes three pairs of equal-diameter wheels 17 whichare mounted on three parallel drive shafts 18 whose axes lie in a commonplane so that three rows of in-line, spaced-apart, wheels are formed.

The peripheries of the wheels 17 are grooved to receive a collar 5 of aholder 1, and adjacent wheels 17 are spaced apart is associated with afirst outer pair of the wheels 17 and the central pair of wheels 17, andasecond burner 20 is associated with the central pair of the wheels 17and the second outer pair of the wheels 17.

At each end of the set of wheels 17 there is a pair of arms 21, thesearms 21 being mounted on two square-sectioned shafts 22, extendingparallel to the shafts 18, so that corresponding arms at each end of theset of wheels 17 are mounted on a common shaft. The arms 21 can beactuated, so that each pair of arms 21 closes and opens, by afoot-actuable air-operated piston and cylinder arrangement 23, operatinglever 24 and meshing gear wheels 25 mounted one on each shaft 22.

The first burner 19 is mounted so as to be stationary in operation ofthe apparatus whereas the second burner 20 is mounted for oscillatingslightly, in the direction along the shafts 18 and 22, about an axis 26under the action of an eccentric driven roller 27 that contacts a roller28 connected by an arm 30 to a post 29 supporting the burner 20. Theroller 27 is driven from one of the shafts 18 via mechanism (not shown)such that the burner oscillates in an out-of-phase relationship with therotation of the wheels 17.

The apparatus described above is utilized as follows. The shafts 18 aredriven to rotate the wheels 17 in the direction indicated by arrows 17'in FIG. 1 and a suitable length of glass tube 2 is placed in a pair ofholders 1. The collars 5 of these holders 1 are placed in the groovedperipheries of the first outer pair and the central pair of the wheels17 so that the tube 2 is supported between the wheels 17. It will beappreciated that the relative positions of the various components of theapparatus are adjustable, as necessary, so that the apparatus can bepreset to accommodate a desired length of tube. The rotating wheels 17rotate the collars 5, and hence the tube 2, in the direction indicatedby arrow 5' in FIG. 1, and the rotating tube 2 is subjected to a firstheating stage by the stationary burner 19.

When the first heating stage (preheating) has been completed, the aircylinder 23 is actuated to cause the arms 21 to close. Initially theleft-hand arm 21 (FIG. 1) of each pair engages the shanks 1' of theholders 1 and moves the holders 1 and hence the tube 2 to the right(FIG. 1), the collars 5 riding over the central pair of wheels 17. Thecentral pair of wheels 17 act on the collars 5 to carry the holders 1and tube 2 on to the right to be received by the right-hand arm 21(FIG. 1) of each pair. The cylinder 23 is actuated to open the arms 21and the right-hand arms guide the holders 1 so that the collars 5 passto be supported by the grooved peripheries of the central pair and thesecond outer pair of the wheels 17. At this stage a second similarlength of tube 2 supported by a pair of holder 1 is placed on thegrooved peripheries of the first outer pair and the central pair of thewheels 17 and subjected to preheating.

Meanwhile the first length of tube 2 is subjected to a second heatingstage, it being heated to a high temperature by the second burner 20which is oscillated while effecting this heat- When the tube 2 beingsubjected to the second heating stage has reached a soft enough state tobe worked upon, it is lifted from the wheels 17, utilizing the holders 1attached to it, and bent, by the operator, to an approximation of thefinal shape to which it is to be bent. This tube 2 is then placed in thearms 8 of the jig, where it is retained by spring clips (not shown),these arms 8 having been preset to a desired position and the nests 12of the jig having been previously positioned such that air can be blowninto the tube 2 from the blocks 16 via the apertures 4. Blowing of airinto the tube 2 is effected by operating a foot valve (not shown).

While the first length of tube 2 is cooling'in the jig, thearms 21 areactuated to move the second length across the wheels 17 to be subjectedto the second heating stage, and a third length of tube 2 is placed onthe wheels 17, utilizing the third pair of holders 1, to be subjected tothe first heating stage. Thereafter the above-described operations arerepeated cycli- In a form of the apparatus not shown equipment isprovided for automatically transferring the tube 2 from the first pairof outer wheels 17 (i.e. from the first heating stage) across thecentral pair to the second pair of outer wheels 17 (Le. to the secondheating stage), this transfer being effected either at predeterminedtime intervals, or in dependence upon the temperature of the precedingtube being subjected to the second heating stage. In this latter caseequipment is provided for automatically sensing the temperature of thetube being subjected to the second heatingstage and the transfer of atube from the second heating stage is arranged to initiate transfer ofthe next following tube to the second heating stage.

It will be appreciated that in the apparatus described the tube that ispassed to the bending jig has been substantially uniformly heated duringthe second heating stage, this uniform heating being assisted by therotation of the tube whilst the source of heat oscillates in thedirection along the length of the tube in out-of-phase relationship withthe rotation of the tube.

The apparatus described can be utilized for heating and bending tubes ofmaterial other than glass, and the part of the apparatus in which thematerial is heated can be utilized for heating tubing that is to beafterwards worked other than by bending, for example by drawing to forma length of tube of reduced diameter, or by enlarging to form abulb-shaped portion.

What we claim is:

1. An apparatus for treating elongated tubular material comprising meansfor rotating the tubular material, a first source of heat for heatingsaid tubular material while the material is rotating, this first sourcebeing arranged to be stationary during operation, a second source ofheat, and means for oscillating this second source of heat substantiallyin the direction of length of said tubular material while said tubularmaterial is rotating; said oscillating means including a support for thesource, a roller, an arm connecting the roller to this support, and adrivable eccentric roller; the first-mentioned roller being arranged torun on the drivable eccentric roller to impart oscillatory motion to thesupport via the arm when the eccentric roller is driven; said materialrotating means including three rows of in-line, spaced-apart, wheels,each of the two pairs of adjacent rows constituted by these three rowsserving for supporting a length of material, and mechanism for rotatingthe wheels so as to rotate a length of material supported thereby; saidfirst heat source being associated with one of the pairs of adjacentrows and said second heat source being associated with the other of thepairs of adjacent rows.

2. An apparatus as claimed in claim 1, wherein the means for rotatingthe material and the means for oscillating the second source of heat arearranged to effect this rotation and oscillation such thatthe heatsource is oscillated, in operation of the apparatus, in an out-of-phaserelationship with respect to the rotation of the material.

3. An apparatus as claimed in claim 1, wherein said eccentric roller isarranged to be driven by said means for rotating the wheels. 7

4. An apparatus as claimed in claim ll comprising a pair of arms at eachend of the three rows of wheels, the corresponding arms at each end ofthe rows of wheels being mounted for pivoting together about a commonaxis, and further comprising means for pivoting the arms about thecommon axes so as to open and close each pair of arms, the arrangementbeing such that a length of material supported by one pair of adjacentrows of wheels can be transferred to be supported by the other pair ofadjacent rows of wheels by closing the arms so that the material isguided by one arm of each pair of arms away from said one pair ofadjacent rows of wheels to be received by the other arm of each pair ofarms, which other arms guide the material to said other pair of adjacentrows of wheels upon subsequent opening of the arms, the material beingtransferred between the arms by rotation of the row of wheels common tothe two pairs of adjacent rows.

S. An apparatus as claimed m claim 4, wherein said means for pivotingthe arms includes a pair of meshing gear wheels, one fast with one armof one of the pairs of arms and the other fast with the other arm ofthis pair of arms, a lever for rotating one of the gear wheels and afluid-operated piston and cylinder arrangement for actuating the leverto rotate said one gear wheel.

6. An apparatus as claimed in claim 1, wherein said wheels are adaptedto support a length of material via holders that are attached to eachend of the length of material.

7. An apparatus as claimed in claim 6, wherein each holder comprises ashank, a clamp carried by the shank and that can be releasably securedto an end of a length of material, and a collar; the peripheries of thewheels being grooved to receive the collars of holders secured one ateach end of a length of material.

8. An apparatus as claimed in claim 7 comprising a bending jig andwherein each holder is adapted for cooperation with said bendingjig,said jig including two arms that can be fixed at various angles withrespect to each other, or parallel to one another at various distancesapart, said arms including members for receiving the collars of a pairof said holders secured one at each end ofa length of material to bebent in thejig.

9. An apparatus as claimed in claim 8, wherein each holder is hollow anddefines an aperture such that air can be blown through the holder into alengthy of tubular material to which the holder is secured.

2. An apparatus as claimed in claim 1, wherein the means for rotatingthe material and the means for oscillating the second source of heat arearranged to effect this rotation and oscillation such that the heatsource is oscillated, in operation of the apparatus, in an out-of-phaserelationship with respect to the rotation of the material.
 3. Anapparatus as claimed in claim 1, wherein said eccentric roller isarranged to be driven by said means for rotating the wheels.
 4. Anapparatus as claimed in claim 1 comprising a pair of arms at each end ofthe three rows of wheels, the corresponding arms at each end of the rowsof wheels being mounted for pivoting together about a common axis, andfurther comprising means for pivoting the arms about the common axes soas to open and close each pair of arms, the arrangement being such thata length of material supported by one pair of adjacent rows of wheelscan be transferred to be supported by the other pair of adjacent rows ofwheels by closing the arms so that the material is guided by one arm ofeach pair of arms away from said one pair of adjacent rows of wheels tobe received by the other arm of each pair of arms, which other armsguide the material to said other pair of adjacent rows of wheels uponsubsequent opening of the arms, the material being transferred betweenthe arms by rotation of the row of wheels common to the two pairs ofadjacent rows.
 5. An apparatus as claimed in claim 4, wherein said meansfor pivoting the arms includes a pair of meshing gear wheels, one fastwith one arm of one of the pairs of arms and the other fast with theother arm of this pair of arms, a lever for rotating one of the gearwheels and a fluid-operated piston and cylinder arrangement foractuating the lever to rotate said one gear wheel.
 6. An apparatus asclaimed in claim 1, wherein said wheels are adapted to support a lengthof material via holders that are attached to each end of the length ofmaterial.
 7. An apparatus as claimed in claim 6, wherein each holdercomprises a shank, a clamp carried by the shank and that can bereleasably secured to an end of a length of material, and a collar; theperipheries of the wheels being grooved to receive the collars ofholders secured one at each end of a length of material.
 8. An apparatusas claimed in claim 7 comprising a bending jig and wherein each holderis adapted for cooperation with said bending jig, said jig including twoarms that can be fixed at various angles with respect to each other, orparallel to one another at various distances apart, said arms includingmembers for receiving the collars of a pair of said holders secured oneat each end of a length of material to be bent in the jig.
 9. Anapparatus as claimed in claim 8, wherein each holder is hollow anddefines an aperture such that air can be blown through the holder into alength of tubular material to which the holder is secured.